Sarah Palin once urged her supporters not to retreat but to reload. In the run-up to last years mid-terms her website carried a map of vulnerable Democrat-held seats, each marked with the cross-hairs of a gun-sight. Sharron Angle, a Republican candidate in that election, once said that the federal government needed second-amendment remedies - the second being the one about the right to bear arms. Right-wing radio and television hosts routinely indulge in the language of armed resistance to the tyranny that resides in Washington, DC, as though Barack Obama were a reincarnation of the hated King George III and they were the heroes of the revolution. None of this is useful or clever - and it is no less awful because the American left is also guilty of crass hyperbole. But it is a big (and so far unjustified) leap to blame the woeful state of American political discourse for the shooting of Gabrielle Giffords, a congresswoman, and the killing of six people in Tucson, Arizona, on January 8th. Worse, by focusing on this issue, America is ignoring the real culprit: its gun laws. It is clearly true that American politics have got a lot nastier in recent years. Politicians and their acolytes no longer treat opponents as decent and honourable, if sadly mistaken, public servants. Liberals blame talk radio and Fox News for this, but leftish websites have proved themselves more than capable of dishing out abuse, sometimes laced with violent imagery, to Mrs Palin, bankers and George Bush. This development is to be deplored (though pious Britons might also note that their politicians cheerfully discussed decapitation strategies at the last election). Such talk certainly makes it harder for Americas two political parties to co-operate in tackling urgent questions such as their nations gargantuan debt, or its slide in the world education rankings. And, in the country with the developed worlds highest murder rate and easiest access to guns, violent political rhetoric that paints government as an enemy to be fought is troubling. The causal relationship between vicious talk and violent action is far less certain. Since the 1960s political violence in America has been mercifully rare. The last killing of a member of Congress came in 1978, and that was in Guyana. The attempted assassination of Ronald Reagan was 30 years ago. Since then only the Oklahoma City bombing, which killed 168 in a federal government building, has spilt blood on Americas political scene, though the election of Barack Obama has prompted death threats from the sort of person who does not believe that a black man is fit to be president, and the contested passage of health-care reform seems to have prompted an increase in death threats against representatives who voted for it. Whether Jared Loughner was part of this trend is arguable. He was evidently politicised: he raved on the internet about the currency and the government. He had met Ms Giffords before and been offended by her failure to answer a nonsensical question he had put to her. The FBI found a note in his home about his assassination, saying I planned ahead. But unlike the killer of Salman Taseer, who said after he murdered the politician last week that he was prompted by Taseers opposition to the blasphemy law, Mr Loughner has not explained himself; and his decision to take the fifth amendment in court this week suggests he may stay silent. Mr Loughner may be politically motivated, but he is also clearly insane - a textbook case of paranoid schizophrenia in the view of a psychologist, and one who had already attracted police attention. He was ejected from an adult mathematics class because he had a habit of yelling that the class was unconstitutional and thought the government was trying to control his grammar. The indiscriminate carnage in Tucson looks more like the killings by a deranged student at Virginia Tech in 2007, or the schoolroom atrocity at Columbine in 1999, than the assassinations of the Kennedys or Martin Luther King. And even if intemperate political language did to some degree help stew Mr Loughners brain - along with violent video games, Goth music and marijuana - there is nothing to be done about it. Rambunctious debate is central to Americas democracy. The first amendment protects free speech even more firmly than the second protects guns - the real villain of the piece, besides the killer himself. Opportunists who seek to gain political advantage by blaming the shootings on words would do America better service if they focused on bullets. In no other decent country could any civilian, let alone a deranged one, legally get his hands on a Glock semi-automatic. Even in America, the extended 31-shot magazine that Mr Loughner used was banned until 2004. As the Brady Centre, established after the Reagan shooting to commemorate one of its victims, has noted, more Americans were killed by guns in the 18 years between 1979 and 1997 than died in all of Americas foreign wars since its independence. Around 30,000 people a year are killed by one of the almost 300m guns in America - almost one for every citizen. Those deaths are not just murders and suicides: some are accidents, often involving children. The tragedy is that gun control is moving in the wrong direction. The Clinton-era ban on assault weapons expired in 2004 and, to his discredit, Mr Obama has done nothing to try to revive it. In 2008 the Supreme Court struck down Washington, DCs ban on handguns, and in 2010 Chicagos went the same way; others are bound to follow. In state after state the direction of legislation is to remove restrictions on gun use (those footling bans on bringing weapons into classrooms or churches or bars), rather than to enhance them. It is fanciful to imagine that guns will ever disappear from America; they are too deeply embedded in its founding myths and its culture. But that does not mean that more effective checks on the mentally unstable are impossible, or that restrictions on the killing power of what can be sold are doomed to failure. Neither of these will happen, though, unless the blame is directed to where it belongs. Economist